Measuring Diffusion and Flux Across a Biological Membrane Capsule

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Measuring Diffusion and Flux Across a Biological
Membrane Capsule

• Gabe Li
• Scott Wasko
• Herb Waite
• Biomolecular Sciences and Engineering Program

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New Methods of Drug Delivery
An encapsulant used to shield Islet tissue from a
diabetic host
Carbon Dioxide
Waste (Urea)
Islets of Langerhans tissue (Pig)
Insulin
Oxygen
Glucose
Immune Attack
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Our Goal/Big Picture

• Many capsules have been tested, but the whelk has
  not yet.
• We want to see if the membrane could be a
  possible encapsulant.
• We need to see which chemicals can permeate the
  capsule, and the rates that they do.

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The Whelk
Unique Self Healing Properties
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Equipment
A Spectrometer measuring Optical Density
An Ussing Chamber
A 96-Well Plate
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Methods
Urea
Capsule

• Put membrane in between Ussing.
• Fill one side of Ussing with a concentrated
  solution of urea or glucose, one with water
• Wait, and take 5µl samples of the water at
  specific time intervals

Less Concentrated
Ussing
More Concentrated
PBS
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Why Glucose and Urea?
Various Solutes
Waste (Urea)
Glucose
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Results-Urea
Estimating Equilibration Time
A Failed Attempt
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Results-Glucose
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Final Graphs
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Analysis

• Using a modified Ficks Equation and an equation
  for flux, we found permeability and flux rates
  for urea and glucose.
• Urea was much more permeable, though this makes
  sense.

Urea J6.175x10-6 mol/s P2.354x10-7 cm/s
Glucose J4.17x10-11 mol/s P5.31x10-12 cm/s
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Conclusion

• Both urea and glucose permeate through the whelk
  egg capsule, albeit glucose is much slower
• Hopefully, after further research, the capsule
  will be deemed a possible candidate for drug
  delivery
• It would then be synthetically mimicked in a lab
  and become a new generation of therapeutic agents

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What I Learned

• Lab work requires patience and care, but is very
  enjoyable.
• Living in Santa Barbara with a grad student
  salary is hard!
• When being chased by a guy dressed as a dinosaur,
  kids move like a school of fish.

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Acknowledgments

• Scott Wasko, for being a great mentor
• Herb Waite, for being a helpful and friendly
  advisor
• Lubi and Anthony for organizing everything
• NIH
• CNSI

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Measuring Diffusion and Flux Across a Biological
Membrane Capsule

• Gabe Li
• Scott Wasko
• Herb Waite
• Biomolecular Sciences and Engineering Program